1. Field
The present embodiments generally relate to systems and methods for producing ammonia. More particularly, embodiments of the present invention relate to systems and methods for recovering heat from a synthesis gas and producing ammonia.
2. Description of the Related Art
Synthesis gas or “syngas” is typically the product of reforming a carbon containing material in the presence of steam and/or an oxidant at high temperatures. Depending on the starting materials, syngas is usually rich in carbon monoxide and hydrogen, and can also contain varying amounts of methane, carbon dioxide, nitrogen, and argon.
Conventional syngas preparation can include introducing a hydrocarbon to a fired steam reformer and contacting the hydrocarbon with a steam reforming catalyst. The primary reformed hydrocarbon is then introduced to a secondary reformer where hydrogen and unreformed hydrocarbons are partially oxidized with an oxidant in the presence of a catalyst. The reforming steps are endothermic and require heat to be supplied to the reformers in order for the reactions to proceed. The heat for the reforming reactions is usually provided by burning large amounts of fuel. Increasing the temperature of the secondary reformer can provide a higher conversion of the hydrocarbon to syngas, but doing so requires oxidizing more fuel.
A need exists, therefore, for systems and methods for converting more of the hydrocarbon to syngas while reducing equipment cost and size, and reducing the amount of fuel required to provide the heat for the reforming reactions.